You need to get the username/password from whoever set up your connection. Most techies will give you something in written when they set up your system. The paper will almost always contain the username/password that they used.

If that isn't the case here, then you need to contact them to get it, or worst case scenario, it's missing and then you need to reset the router and set up everything again.

DO NOT try to reset it yourself, unless you know exactly what you are doing. You will need to fill in some info, just to be able to connect to your Internet.